Conventional methods for the immunological measurement using rabbit IgG and anti-rabbit IgG as reference antibodies use biochips in which a probe specifically binding to a material to be tested and a probe specifically binding to a rabbit antibody are fixed in a conjugate zone, a capture antibody against the material to be tested is fixed in a test zone, and an anti-rabbit antibody is fixed in a reference zone (WO 2013/125855). However, when a sample is quantified using the reference antibody, measured values may be varied by factors such as differences in viscosity and components caused by large amounts of materials present in the sample, and non-specific reactions by anti-rabbit antibodies and the like although the same amount of the sample is injected. Also, when conventional reference antibodies are used, errors in amount of the sample upon injection of the sample may occur, and the temperature of the sample and/or device may increase or decrease by an environment in which the sample is measured. Therefore, there is a probability in which the values in the test zone may vary always. In addition, the binding affinity of the antibodies in the test and reference zones may be varied by the factors as described above.
Meanwhile, a hapten is a material against which there are no antibodies in the human body since the material causes no immune response per se. When haptens of toxic components which cannot be present in the human body are used, a non-specific reaction is expected to hardly occur in the sample. Also, antibodies having different affinity constants against the hapten have different antigen binding affinities at various temperatures. However, there is no case in which the antibodies binding to the hapten exhibiting such characteristics are used as reference antibodies as far.
Therefore, the present inventors have developed an method for the immunological measurement including a reference antibody which includes a hapten and an antibody binding to the hapten, wherein the method for the immunological measurement is able to improve accuracy in quantitative measurement by supplementing a result value according to parameters of user environments and reducing a non-specific reaction with a sample. Therefore, the present invention has been completed based on the facts.